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In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation
![File:William Hammer - A still life with strawberries in a bowl and radishes, asparagus and a head of lettuce resting on a wooden table (1848).jpg - Wikimedia Commons File:William Hammer - A still life with strawberries in a bowl and radishes, asparagus and a head of lettuce resting on a wooden table (1848).jpg - Wikimedia Commons](https://upload.wikimedia.org/wikipedia/commons/6/6b/William_Hammer_-_A_still_life_with_strawberries_in_a_bowl_and_radishes%2C_asparagus_and_a_head_of_lettuce_resting_on_a_wooden_table_%281848%29.jpg)
File:William Hammer - A still life with strawberries in a bowl and radishes, asparagus and a head of lettuce resting on a wooden table (1848).jpg - Wikimedia Commons
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In Uncle Sam's Service: WWI Inventor William J. Hammer | Lemelson Center for the Study of Invention and Innovation
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File:William Hammer - Still-life of figs in a basket and fruit on a ledge (1855).jpg - Wikimedia Commons
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